Tetracycline sensitizes TiO2 for visible light photocatalytic degradation via ligand-to-metal charge transfer

Treatment of antibiotics contaminated water remains a global environmental challenge. In this study, tetracycline (TC) was found to effectively sensitize pure TiO2 for visible light photocatalytic degradation via a ligand-to-metal charge transfer mechanism. The sensitization was attributed to the formation of TC-TiO2 complex and the overlap of the molecular orbitals of TC and the conduction band of TiO2. The intermediate degradation products of TC, however, did not sensitize TiO2, which was the reason for the low mineralization rate. Nevertheless, our results showed that the intermediate degradation products of TC had significantly reduced bactericidal effects and less induction of antibiotic-resistance genes (ARGs). This study showcases an effective treatment of antibiotics-containing wastewater using the most common photocatalyst TiO2 with reduced risk in the spread of ARGs. (c) 2022 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

This study found that tetracycline can effectively sensitize pure TiO2 for visible light photocatalytic degradation through a charge transfer mechanism. The intermediate degradation products of tetracycline show reduced bactericidal effects and less induction of antibiotic-resistance genes. This study demonstrates an effective method for treating antibiotics-contaminated wastewater using TiO2.